It used to be that anything below sea level just showed up as blue ocean on Google Earth. But starting February 2, viewers will be able to see what is under the water, using an upgraded version of Google Earth.

In addition to the underwater imagery, a feature called Historical Imagery allows users to scroll back through decades of satellite images and watch developing sprawl, destruction from hurricanes, reforestation, or coastal erosion. A new function called Touring allows the user to create virtual tours on land or below the sea surface to depict a route for a hike or scuba excursion. The new version of Google Earth can be downloaded for free at http://earth.google.com.